A few questions here,

1. What do you do to get this error?
2. If its specific pages can you share the link?
3. Are you able to do this in another browser? Which one?

That unusual error code has this explanation in the source code:

"An X.509 version 1 certificate that is not a trust anchor was used to issue the server’s certificate. X.509 version 1 certificates are deprecated and should not be used to sign other certificates."

You shouldn't get this error on modern websites. Is the problem when you try to connect to an old device that hasn't been updated for several years?